1. Field of the Invention
The present invention relates to a sandwich panel.
2. Description of the Related Art
Honeycomb sandwich panels disclosed in Examined Utility Model Application Publication No. 6-17530 or the like have been used in the past. In such honeycomb sandwich panels, carbon (C) fiber-reinforced plastic bodies are laminated as middle layers onto both upper and lower surfaces (both open end surfaces) of a honeycomb core in which hollow columnar cells are aggregated in a plane, and surface members are laminated on the carbon (C) fiber-reinforced plastic bodies.
Since lightness of weight is associated with better performance in terms of the fuel consumption of aircraft or the like, the weight of the structural and interior materials needs to be reduced. The honeycomb sandwich panel described above, in which fiber-reinforced plastic panels are placed above and below a honeycomb core, is used as a material that yields such a reduction in weight.
In particular, an inner wall material, which is one of the interior materials used in aircraft, is required not only to be lightweight, but also to satisfy flexural strength and in-plane shear strength requirements as a sandwich panel. These characteristics, however, cannot be met merely by changing the amount of fibers or by changing the number of fiber layers that constitute the middle layer.